diff --git a/lib/arm/arm_machine.rb b/lib/arm/arm_machine.rb
index 0eba5447..d5bcb561 100644
--- a/lib/arm/arm_machine.rb
+++ b/lib/arm/arm_machine.rb
@@ -14,6 +14,10 @@ module Arm
       block <<  cmp( left ,  right )
       Vm::BranchCondition.new :le
     end
+    def integer_less_than block ,  left , right
+      block <<  cmp( left ,  right )
+      Vm::BranchCondition.new :lt
+    end
     def integer_greater_than block ,  left , right
       block <<  cmp( left ,  right )
       Vm::BranchCondition.new :gt
diff --git a/lib/ast/if_expression.rb b/lib/ast/if_expression.rb
index 29b30854..d67c2c87 100644
--- a/lib/ast/if_expression.rb
+++ b/lib/ast/if_expression.rb
@@ -11,5 +11,31 @@ module Ast
     def attributes
       [:cond, :if_true, :if_false]
     end
+    def compile context , into
+      false_block = into.new_block "#{into.name}_else"
+      merge_block = false_block.new_block "#{into.name}_if_merge"
+
+      cond_val = cond.compile(context , into)
+      puts "compiled if condition #{cond_val.inspect}"
+      into.b false_block , condition_code: cond_val.not_operator
+            
+      last = nil
+      if_true.each do |part|
+        last = part.compile(context , into )
+        puts "compiled in if true #{last.inspect}"
+      end
+      
+      into.b merge_block
+
+      if_false.each do |part|
+        last = part.compile(context , false_block )
+        puts "compiled in if false #{last.inspect}"
+      end
+      
+      puts "compile if end"
+      into.insert_at merge_block
+
+      return last
+    end
   end
 end
\ No newline at end of file
diff --git a/lib/ast/operator_expressions.rb b/lib/ast/operator_expressions.rb
index b235e035..223c7364 100644
--- a/lib/ast/operator_expressions.rb
+++ b/lib/ast/operator_expressions.rb
@@ -37,6 +37,8 @@ module Ast
       case operator
       when ">"
         code = l_val.greater_than into , r_val
+      when "<"
+        code = l_val.less_than into , r_val
       when "+"
         res = context.function.new_local
         into.res = l_val + r_val
diff --git a/lib/vm/values.rb b/lib/vm/values.rb
index 72a95518..277ebe95 100644
--- a/lib/vm/values.rb
+++ b/lib/vm/values.rb
@@ -38,6 +38,8 @@ module Vm
         :gt
       when :gt
         :le
+      when :lt
+        :ge
       else
         raise "no implemented #{@operator}"
       end
@@ -96,6 +98,9 @@ module Vm
     def greater_than block , right
       RegisterMachine.instance.integer_greater_than block , self , right
     end
+    def less_than block , right
+      RegisterMachine.instance.integer_less_than block , self , right
+    end
     def == other
       code = class_for(CompareInstruction).new(self , other , opcode: :cmp)
     end
diff --git a/test/fragments/test_if.rb b/test/fragments/test_if.rb
index 34867e09..dc16aa56 100644
--- a/test/fragments/test_if.rb
+++ b/test/fragments/test_if.rb
@@ -12,9 +12,9 @@ class TestIf < MiniTest::Test
         putstring("else")
       end
     end
-    itest(10)
+    itest(20)
 HERE
-    @should = [0x0,0xb0,0xa0,0xe3,0xa,0x0,0xa0,0xe3,0x1,0x0,0x0,0xeb,0x1,0x70,0xa0,0xe3,0x0,0x0,0x0,0xef,0x0,0x40,0x2d,0xe9,0x0,0x10,0xa0,0xe3,0x1,0x20,0xa0,0xe3,0x1,0x0,0x50,0xe3,0x6,0x0,0x0,0xda,0x1,0x30,0xa0,0xe1,0x2,0x10,0xa0,0xe1,0x2,0x40,0x83,0xe0,0x4,0x20,0xa0,0xe1,0x1,0x50,0x40,0xe2,0x5,0x0,0xa0,0xe1,0xf6,0xff,0xff,0xea,0x3f,0x0,0x2d,0xe9,0x2,0x0,0xa0,0xe1,0x12,0x0,0x0,0xeb,0x3f,0x0,0xbd,0xe8,0x0,0x80,0xbd,0xe8,0x0,0x40,0x2d,0xe9,0xa,0x20,0x41,0xe2,0x21,0x11,0x41,0xe0,0x21,0x12,0x81,0xe0,0x21,0x14,0x81,0xe0,0x21,0x18,0x81,0xe0,0xa1,0x11,0xa0,0xe1,0x1,0x31,0x81,0xe0,0x83,0x20,0x52,0xe0,0x1,0x10,0x81,0x52,0xa,0x20,0x82,0x42,0x30,0x20,0x82,0xe2,0x0,0x20,0xc0,0xe5,0x1,0x0,0x40,0xe2,0x0,0x0,0x51,0xe3,0xef,0xff,0xff,0x1b,0x0,0x80,0xbd,0xe8,0x0,0x40,0x2d,0xe9,0x0,0x10,0xa0,0xe1,0x24,0x0,0x8f,0xe2,0x9,0x0,0x80,0xe2,0xe9,0xff,0xff,0xeb,0x18,0x0,0x8f,0xe2,0xc,0x10,0xa0,0xe3,0x1,0x20,0xa0,0xe1,0x0,0x10,0xa0,0xe1,0x1,0x0,0xa0,0xe3,0x4,0x70,0xa0,0xe3,0x0,0x0,0x0,0xef,0x0,0x80,0xbd,0xe8,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x0]
+    @should = [0x0,0xb0,0xa0,0xe3,0x14,0x0,0xa0,0xe3,0x1,0x0,0x0,0xeb,0x1,0x70,0xa0,0xe3,0x0,0x0,0x0,0xef,0x0,0x40,0x2d,0xe9,0xc,0x0,0x50,0xe3,0x5,0x0,0x0,0xaa,0x1,0x0,0x2d,0xe9,0x40,0x0,0x8f,0xe2,0x8,0x10,0xa0,0xe3,0x7,0x0,0x0,0xeb,0x1,0x0,0xbd,0xe8,0x4,0x0,0x0,0xea,0x1,0x0,0x2d,0xe9,0x30,0x0,0x8f,0xe2,0x8,0x10,0xa0,0xe3,0x1,0x0,0x0,0xeb,0x1,0x0,0xbd,0xe8,0x0,0x80,0xbd,0xe8,0x0,0x40,0x2d,0xe9,0x1,0x20,0xa0,0xe1,0x0,0x10,0xa0,0xe1,0x1,0x0,0xa0,0xe3,0x4,0x70,0xa0,0xe3,0x0,0x0,0x0,0xef,0x0,0x80,0xbd,0xe8,0x74,0x68,0x65,0x6e,0x0,0x0,0x0,0x0,0x65,0x6c,0x73,0x65,0x0,0x0,0x0,0x0]
     parse 
     write "if"
   end